A guinea pig-sized rodent last seen in 1898 showed up at a nature reserve eco-lodge in Colombia earlier this month. Volunteers at the El Dorado Nature Reserve noticed the creature, a red-crested tree rat (Santamartamys rufodorsalis), on a handrail at 9:30pm on May 4. The 18-inch-long rodent stayed for a couple of hours before disappearing back into the forest.

“He just shuffled up the handrail near where we were sitting and seemed totally unperturbed by all the excitement he was causing,” said Lizzie Noble from Godalming, England, one of the two volunteers who spotted the creature. Paul Salaman, a scientist from the World Land Trust-US, confirmed the identity of the species, which is known from only two skin specimens.

The rat will now likely be designated as critically endangered (before this discovery, the IUCN didn’t have enough data to categorize the species), according to a press release.

The reserve itself was established in 2005 by Colombian bird conservation group Fundación ProAves , with support from American Bird Conservancy, World Land Trust-US, the U.S. Fish and Wildlife Service’s Neotropical Migratory Bird Conservation Act, Fundación Loro Parque, and Conservation International.

"We are so proud that our El Dorado Nature Reserve has provided a safe haven for this enigmatic little guy to survive," said Lina Daza, executive director of ProAves. "The discovery exemplifies why we buy forested properties known to be important for endangered wildlife yet at imminent risk of being destroyed."

It’s worth noting that the FWS’s Neotropical Migratory Bird Conservation Act helped support the creation of the reserve. In the May-June issue of Audubon, reporter Nick Neely writes about the vital importance of the legislation, noting that the western tanager (right) is among the more than 340 bird species whose far-flung habitats it has helped conserve in the United States, Canada, Latin America, and the Caribbean. Unfortunately, the funding authorization expired last year; as a result, funding for 2011 and beyond is uncertain.

To send a letter to your U.S. Representative and Senators asking them to support legislation to reauthorize the Neotropical Migratory Bird Conservation Act, click here. As the red-crested tree rat’s appearance shows, the legislation helps conserve birds and so much more.